1. Self study

2. If statements

3. Selection Structure if selection statement if…else selection statement
switch selection statement

4. Example ... if ( grade >= 60 ) System.out.print("Passed”);
Write a program that reads a student’s grade and prints “passed” if the grade is greater than or equal 60.
Flowchart:
Code:
...
if ( grade >= 60 )
System.out.print("Passed”);

5. One-Way Selection Example: char grade=‘’ if ( score >= 90 )
grade = ‘A’;

6. Example if-statement: find absolute value
import java.util.Scanner;
public class If1 {
public static void main(String[] args)
Scanner in = new Scanner(System.in);
int a;
System.out.print("Enter an integer value: ");
a = in.nextInt(); // Read in an integer from keyboard
if ( a < 0 ) // If-statement
a = -a; // Negate a ONLY if a < 0
System.out.print("It's absolute value = ");
System.out.println(a); }

7. Two-Way Selection Syntax: if (expression) statement1; else statement2;
else statement must be paired with an if.

8. Two-Way Selection Example: boolean positive, negative;
if (number >= 0 )
positive = true;
else //number < 0
negative =true;

9. Multiple Selection: Nested if
Example4_23 :
if ( GPA >= 2.0 )
if (GPA >= 3.9)
System.out.println(“Dean Honor list”);
else
System.out.println(“GPA below graduation requirement”);
If GPA = 3.8 what will be printed?
GPA below graduation requirement

10. Multiple Selection: Nested if
Example4_23 : (rewritten)
if ( GPA >= 2.0 ) {
if (GPA >= 3.9)
System.out.println(“Dean Honor list”); }
else
System.out.println(“GPA below graduation requirement”);
Now, if GPA = 3.8 what will be printed?

11. public class Test { public static void main(String args[]){ int x = 30; if( x == 10 ){ System.out.print("Value of X is 10");} else if( x == 20 ){ System.out.print("Value of X is 20");} else if( x == 30 ){ System.out.print("Value of X is 30");} else{ System.out.print("This is else statement"); }

13. Exercise
What is the output for the following code lines if hours=35 and hours=60:
a) if (hours <= 40)
System.out.println(“No overtime” );
System.out.println(“ You must work over 40 hours for overtime\n”);
System.out.println(“Continue” );
B) if (hours <= 40) {
cout << “No overtime” << endl;
cout << "You must work over 40 hours for overtime.\n"; }
cout << “Continue” << endl;